My issue is around 8000-9000 RPM, the bike feels like one or two cylinders miss temporarily. Power is reduced, and she sputters until she turns up a bit higher. I've tried running the mixture screws out to 3.25 turns out, and I've tried swapping my K&N filter for an OEM, and neither seems to fix the issue. If anything it currently runs better with the K&N, but not by a lot. It runs pretty well everywhere else in the RPM range, but 8-9K is a horrible spot to have a power loss.

Suggestions? Needles? Check the floats? Change the mixture? I haven't pulled the plugs recently, should I do so?

I was gonna post a thread similar to this but i forgot lol. hopefully we get a lot of people replying so this could be a first gen carb database. instead of power commander maps this is what we have...

anyway here are my mods:
Leo Vince slipon
Factory Pro 1.0 jet kit (with 152/148 main jets and stock pilot)
airbox modified (restrictor cut out, and the only air entering the box is from the air ducts up front and the side carb hoses.)
YEC pressurized float bowl clone mod

It was running very lean (plugs were white and there was surging at certain RPMs) so i raised the float level a bit which made it run much smoother. I still have a little tuning to do because I dont believe the needles should be on the 5th notch...

As for your problem Rad33, try lowering the clips on the needles so it runs a little richer. 8-9k is part of the RPM range that the needles heavily affect. Also if you pull your plugs and look at the color of the carbon buildup, it will give a good indication of how rich/lean your engine is running.

Still workin the bugs outta mine too.. It runs like a raped date at WOT all the way to the rev limiter. Breaks up a hair at part throttle when maintaining speed, and around 8k, I get a nice surge of power, and burping the gas shows a mild hesitation below 9k.

Still workin the bugs outta mine too.. It runs like a raped date at WOT all the way to the rev limiter. Breaks up a hair at part throttle when maintaining speed, and around 8k, I get a nice surge of power, and burping the gas shows a mild hesitation below 9k.

Sounds just like my bike. Is it even possible to get a carbed bike to run well at low rpm/part throttle AND run very well at wide open throttle? Its like its either one or the other from what i've noticed

Sounds just like my bike. Is it even possible to get a carbed bike to run well at low rpm/part throttle AND run very well at wide open throttle? Its like its either one or the other from what i've noticed

Hahahaaha I'll let you know. I will definitely get it perfect with a little more effort. Personally, I think the real problem is us putting in these jet kits. None of em come with pilot jets, the needles have play in them, they dont sit nicely like the stock ones with the big cap at the top.

If I can't get it nice after adjusting the needles and going way rich on the pilot adjusters, I am going to order different pilot jets. I think there is only so far you can go by adjusting the screw. And then I'll go back to factory needles but will shim them up for finer adjust-ability. A guy who owns a reputable shop by me has told me a few times that the stock needles with shims are the only way to go.

So I finally got around to pulling the plugs today. If anything, I'd say it looks like I'm running rich. All four plugs looked identical. Not the nice tan color I'd like to see, and not white-ish indicating running lean, but slightly darker/sooty color. Still figure I should try going a bit richer on the needles?

So I finally got around to pulling the plugs today. If anything, I'd say it looks like I'm running rich. All four plugs looked identical. Not the nice tan color I'd like to see, and not white-ish indicating running lean, but slightly darker/sooty color. Still figure I should try going a bit richer on the needles?

It's hard to say. I would try going riche on the needles cause I feel like the bog is aused by that. Lookin at the plugs is a good way to see overall perormance/mixture.

The plug would really indicate your main jetting setting. Since that's what the bike really sees.

with the factory pro kit the guy from factory pro said their needles seem to be rich, but you have the ivans. Despite what the factory pro guys said I'm gonna try and go richer. I'm 1 clip from as lean as possible now

2.5 out and clip on 5th down from top. It runs great 8K+ but bottom seems like it can do some work, occasional bog and crummy start from stop. just replaced plugs and the old one seems rich, carbon build up and one of them seems wet a bit, not too much. Im gonna try to move to fourth clip and see how it runs tomorrow.

2.5 out and clip on 5th down from top. It runs great 8K+ but bottom seems like it can do some work, occasional bog and crummy start from stop. just replaced plugs and the old one seems rich, carbon build up and one of them seems wet a bit, not too much. Im gonna try to move to fourth clip and see how it runs tomorrow.

Let us know. I was thinking 5th clip?! Really? That's really rich, but with the BMC that just may be how it needs to be. How's it run with the BMC? I am finding my bike is running lean when it's cold out. I guess different/larger main jets before the fall comes..

So with the 4th clip it feels a bit dif but not by much around the mid. I guess it'll save me some MPGs. I found out 2 of my float needle were just not good and leaking fuel slooowly and I cleaned it up a bit and it has gotten better. Last week I opened the carb and looked to find pools of gas on top of the valve. The idle is better, no more hanging before dropping. Doing the blip test now show signs of being lean at idle so im gonna try and do 3 turns out and see how it goes. My exhaust decided to snap off at the collector too so its loud and I loosing power. Sounds great and runs like a mad man in high RPM though haha.

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